<th class="aikau-lists-views-layouts-HeaderCell mdl-data-table__cell--non-numeric" data-dojo-attach-point="containerNode" data-dojo-attach-event="ondijitclick:onSortClick" tabindex="0">
   <span class="label" data-dojo-attach-point="labelNode">${label}</span>
   <i class="material-icons" data-dojo-attach-point="ascendingSortNode">arrow_downward</i>
   <i class="material-icons" data-dojo-attach-point="descendingSortNode">arrow_upward</i>
</th>